AkWarm logo.

Innovative, user-friendly, Windows-based software for home energy modeling. AkWarm is designed for weatherization assessment and the EPA Energy Star Home energy rating program. Features include: Graphical display of energy use by building component, improvement options analysis, design heat load, calculates CO2 emissions, and shows code compliance. Utility, weather data, and other libraries are maintained in a database library for easy updating. A separate database is available to archive all input and output data for detailed analysis of housing types, trends, amd energy use.


home energy rating systems, home energy, residential modeling, weatherization



Expertise Required

Basic understanding of building construction, with a minimal level of computer skills.


Approximately 250 weatherization providers, HERS raters, builders, code compliance officials, architects and engineers in Alaska.


Low-income weatherization programs, HERS providers, code officials, builders, designers, and other housing industry professionals.


Client info, geographic location and site details, construction characteristics for above and below grade components, heating system efficiencies, building air tightness, and ventilation strategies, major appliances and electrical use. Software provides pull-down menus for most inputs. Defaults for typical building and mechanical systems provide users with quick data entry and results.


Home Energy Rating certificate, projected annual energy use by units of fuel and cost, graphical breakout of energy use by building component, Energy Features Report listing building component efficiencies, solar and internal heat gain components, design heat loads estimate, Improvement Options report, and Code Compliance verification. On screen "What - if ? " evaluations are available using the cost by component graph feature.

Computer Platform

IBM PC, Windows 3.1 or higher, 4 MB RAM minimum, 5 MB of free disk space, VGA or higher resolution video adaptor.

Programming Language

Visual Basic


First-time users find the input screens and layout less intimidating than the other energy analysis programs currently available. AkWarm offers an excellent balance of user inputs and programmed default values to assure consistent and reliable results, while maintaining a quick and simple program for new and experienced users. Libraries are easily modified by users and are password protected. Add-on reports can be readily developed within wordprocessing or spreadsheet programs. AkWarm has been validated extensively against DOE-2 for cold climate conditions.


Simplified HVAC modeling with no cooling load calculations. Design heat load calculations for only single zones. Solar inputs minimized for northern climates.



Alaska Housing Finance Corporation


P.O. Box 101020
Anchorage, Alaska 99510-1020
United States


(907) 330-8166


(907) 338-1747





Free fully functional demonstration software available upon request. Demonstration software can also be downloaded from www.absn.com . Access to source code, misc. utilities, technical assistance for software enhancements require a no-cost licensing agreement, available only to state agencies upon request. Limited funds available for training and technical assistance. Contact the above for further information.